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Monday, March 19, 2018

CBET nr. 4494, issued on 2018, March 16, announces the discovery of an apparently asteroidal object (magnitude ~17) in the course of the "Asteroid Terrestrial-impact Last Alert System" (ATLAS) search program on CCD images obtained with a 0.5-m f/2 Schmidt reflector at Haleakala, Hawaii. Posted on the Minor Planet Center's PCCP webpage, it has been reported as showing cometary activity by CCD astrometrists elsewhere. The new comet has been designated C/2018 E1 (ATLAS).

I performed follow-up measurements of this object, while it was still on the PCCP webpage. Stacking of 5 unfiltered exposures, 60 seconds each, obtained remotely on 2018, March 12.4 from Q62 (iTelescope network) through a 0.70-m f/6.6 reflector + CCD, shows that this object is a comet with a diffuse coma about 5 arcsec in diameter. The FWHM of this object was measured about 20% wider than that of nearby field stars of similar brightness.

Friday, February 9, 2018

On February 06, 2018 at 20:45 UT, SpaceX successfully launched the Falcon Heavy, a reusable super heavy-lift launch vehicle, introduced as the most powerful rocket currently in operation.

The dummy payload for this test flight was a sports car owned by SpaceX CEO Elon Musk, a midnight cherry, first generation Tesla Roadster. It was selected as "something fun and without irreplaceable sentimental value" to be launched into space on the maiden flight of the Falcon Heavy rocket. The purpose of including the Roadster on the maiden flight was to demonstrate that the Falcon Heavy can launch payloads as far as the orbit of Mars.

Sitting in the driver's seat of the Roadster is "Starman", a dummy astronaut clad in a SpaceX spacesuit. He has his right hand on the steering wheel and left elbow resting on the open window sill. Starman is named for the David Bowie song "Starman". The car's sound system was looping the symbolic Bowie songs "Space Oddity" and "Life on Mars?". A copy of Douglas Adams' 1979 novel "The Hitchhiker's Guide to the Galaxy" is in the glovebox, along with a towel and a sign on the dashboard that reads "Don't Panic!" (two references to the book).

On February 09.4, 2018 I performed follow-up of the #Starman #TeslaRoadster (officially designated 2018-017A) remotely from MPC code H06 (Mayhill, New Mexico; iTelescope network) through a 0.25-m f/3.4 reflector + CCD. Click on the image below for a bigger version.

While below you can see a short animation showing the motion of Starman in about 20 minutes. Each frame is a 60-second exposure. North is up, East to the left.

In the hours after the successful Falcon Heavy launch, a live video feed
of the Roadster and Starman from three cameras mounted inside and on
booms attached to the outside of the vehicle was broadcast on YouTube.
It was expected to last for about twelve hours until the on-board
batteries were depleted; however, the livestream lasted for just over
four hours. Full video stream of the car as it creates spectacular views of Earth from space is still available, see Youtube video below.

Thursday, February 8, 2018

During the 5-month period Aug through Dec 2017, 22 new comets were discovered, cometary activity was detected for 5 previously discovered object (earlier designated as an asteroid) and there were 5 comet recoveries. "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here). See below for the "Other news" section.

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram) which reported the official news & designations.

Aug 03 Following the announcement on CBET 4415 of the possible connection of 2017 MB_1 and the alpha Cap meteor shower, P. Birtwhistle, Great Shefford, Berkshire, England, re-examined his CCD images of 2017 MB_1 taken using a 0.40-m Schmidt-Cassegrain reflector on several dates. There are no traces of cometary activity on co-added exposures taken on July 4.04 (10 min exposure time) and 5.04 UT (30 min total exposure), but on July 25.11, stacked exposures totalling 7.2 min show a possible very faint, thin, straight tail in p.a. 260 deg, appearing detached from the main object, starting at a distance of 35" and extending to 90" from 2017 MB_1. The images from July 25 were taken in brightening nautical twilight (solar altitude -12.8 to -12.0 degrees), but he is reasonably confident that the possible tail is real and not an artifact.

* Further to CBET 4298, G. V. Williams (Minor Planet Center) has linked a reported comet from 2007 to comet P/2016 P2. The comet has been given the permanent number 351P and year designations P/2016 P2 = P/1998 U8 = P/2007 R11.

Further to CBETs 4376 and 4439, the following permanent numbers have been assigned to short-period comets based upon their being securely observed at multiple returns to perihelion.

Sep 20 NASA’s Hubble Space Telescope helped an international team of astronomers find that an unusual object in the asteroid belt is, in fact, two asteroids orbiting each other that have comet-like features. These include a bright halo of material, called a coma, and a long tail of dust. The time-lapse video below, assembled from a set of Hubble Space Telescope photos, reveals two asteroids orbiting each other that have comet-like features. The asteroid pair, called 2006 VW139/288P, was observed in September 2016, just before the asteroid made its closest approach to the Sun.

Oct 25 The first clear case of an interstellar object A/2017 U1. According to CBET 4450 "inadvertently designated as comet C/2017 U1 on MPEC 2017-U181 (and changed to A/2017 U1) with no claimed cometary appearance by anyobservers appears to have hyperbolic orbital elements". A/2017 U1 was discovered Oct. 19 by the University of Hawaii's Pan-STARRS 1 telescope on Haleakala during the course of its nightly search for Near-Earth Objects for NASA. appears to have originated from outside the solar system, coming from somewhere else in our galaxy. If so, it would be the first "interstellar object" to be observed and confirmed by astronomers. According to MPEC 2017-V17: "the object A/2017 U1 receives the permanent designation 1I and the name ʻOumuamua. The name, which was chosen by the Pan-STARRS team, is of Hawaiian origin and reflects the way this object is like a scout or messenger sent from the distant past to reach out to us (ʻou means reach out for, and mua, with the second mua placing emphasis, means first, in advance of). Correct forms for referring to this object are therefore: 1I; 1I/2017 U1; 1I/ʻOumuamua; and 1I/2017 U1 (ʻOumuamua).

Saturday, January 20, 2018

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Circinus (TOCP Designation: PNV J13532700-6725110) I performed some follow-up of this object through a TEL 0.43-m f/6.8 reflector + CCD from MPC Code Q62 (iTelescope Observatory, Siding Spring).

On images taken on January 20.6, 2018 I can confirm the presence of an optical counterpart with R-filtered CCD magnitude +8.09 & V-filtered CCD magnitude +8.33 at coordinates:

An animation showing a comparison between the confirmation image and the archive POSS2/UKSTU Red plate (1997-03-31). Click on the animation for a bigger version:

UPDATE - January 31, 2018

According to CBET 4482 issued on January 30, Spectroscopy by Strader et al., obtained with the 4.1-m Southern Astrophysical Research Telscope (+ Goodman spectrograph) at Cerro Pachon, Chile, on Jan. 21.28 UT shows clear P-Cyg profiles in the Balmer lines, with the absorption troughs located about 1300 km/s blueward of the rest wavelength (emission FWHM about 1500 km/s), and a number of Fe II lines (some of which also have P-Cyg profiles) -- suggestive of a "Fe II"-type nova. See also ATel #11209. While a low-resolution spectroscopic image by S. Kiyota that shows a strong hydrogen emission line is available here.

Monday, January 15, 2018

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Musca (TOCP Designation: PNV J11261220-6531086) we performed some follow-up of this object through a TEL 0.50-m f/6.8 reflector + CCD + focal reducer from MPC Code Q62 (iTelescope Observatory, Siding Spring).

On images taken on January 15.57, 2018 we can confirm the presence of an optical counterpart with R-filtered CCD magnitude ~6.3 at coordinates:

R.A. = 11 26 14.95, Decl.= -65 31 24.1

(equinox 2000.0; Gaia DR1 catalogue reference stars).

This transient has been reported to CBAT/TOCP by Rob Kaufman, Bright, Victoria, Australia. Discovery image (taken with Canon 650D & 55mm lens) is available here. He also posted a low-resolution spectrum that "shows strong hydrogen emissions as well as FeII lines":

Credit: R. Kaufman

Below you can see our confirmation image (single 30-sec exposure through a 0.43-m f/6.8 reflector + CCD), click on it for a bigger version:

An animation showing a comparison between our confirmation image and the archive POSS2/UKSTU Red plate (1998-03-19). Click on it for a bigger version:

UPDATE - January 16, 2018

According to CBET 4472 this transient could be a classical "Fe II"-type nova and it has been designated NOVA MUSCAE 2018.

Friday, December 8, 2017

On December 08, 2017 B. Skiff reported on mpml mailing list, that the centaur 174P/Echeclus (also known as 60558 Echeclus) "seems to be at least 4 mag brighter than expected, and indeed as it appeared at the start of last night's images. The Dec 7 series shows the outburst in progress on images taken near 2:00 and 2:48 UT; it is much brighter now (Dec 8 about 3:30 UT)". Last observations before this outburst had this object at around magnitude 18.

Prompted by this alert, I perfomed some follow-up of 174P/Echeclus and I can confirm that this object is experiencing a bright phase. Unfiltered exposures, 30-seconds each, obtained remotely from Q62 (iTelescope network) on 2017, December 08.57 (through a 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer) reveal 174P as a bright featureless star-like object of magnitude ~14.1 N (click on the image below for a bigger version).

This very interesting object was discovered by Spacewatch in 2000 and initially classified as a minor planet with provisional designation 2000 EC98 (its final minor planet designation is 60558 Echeclus). The presence of coma around it was first detected by Choi and Weissman (2006) on 2005 December 30.50 UT with the Palomar 5m telescope. Soon after, the object was given the periodic comet designation 174P/Echeclus. During the years, it experienced many outbursts. You can find info and images on all these past bright phases on this blog.

Sunday, November 12, 2017

During the month of July 2017, 2 new comets were discovered and cometary activity was detected for 1 previously discovered object (earlier designated as an asteroid). "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here). See below for the "Other news" section.

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram) which reported the official news & designations.

* Note on CBET 4426 issued on August 26: After considerable discussion, the IAU "Working Group for Small Body Nomenclature" (formerly the IAU "Committee for Small Body Nomenclature" and the IAU "Small Bodies Names Committee") has decided to accept the name "ASASSN" for comet C/2017 O1 (cf. CBET 4414).

Jul 12 CBET 4413 report the discovery of an apparent satellite (S/2017 (113) 1) of minor planet (113) Amalthea from observations made of the Tycho Catalogue star 1878-01081-1 (magnitude V = 10.0) during an occultation by the minor planet (which was at V = 12.9) on 2017 Mar. 14.167 UT. A total of ten observation sites recorded seven positive events and three negative events for (113), two of which are attributed to the possible satellite.

Comets & Asteroids news

Welcome to our Astronomy blog, devoted in particular to Comets & Asteroids and related topics. This blog is maintained by Italian amateur astronomer Ernesto Guido, particularly active in the study of the small bodies of the Solar System.